Glossary 11ROMAcronym for read-only memory. Your computer containssome programs essential to its operation in ROM code.Unlike RAM, a ROM chip retains its contents even afteryou turn off your computer. Examples of code in ROMinclude the program that initiates your computer’s bootroutine and the POST.rpmAbbreviation for revolutions per minute.RTCAbbreviation for real-time clock. Battery-powered clockcircuitry inside the computer that keeps the date and timeafter you turn off the computer.SCSIAcronym for small computer system interface. An I/O businterface with faster data transmission rates than standardports. You can connect up to seven devices to one SCSIinterface.SDMSAbbreviation for SCSI device management system.SECCAbbreviation for single-edge connector cartridge.secAbbreviation for second(s).serial portAn I/O port used most often to connect a modem or a mouseto your computer. You can usually identify a serial port onyour computer by its 9-pin connector.shadowingA computer’s system and video BIOS code is usuallystored on ROM chips. Shadowing refers to the perfor-mance-enhancement technique that copies BIOS code tofaster RAM chips in the upper memory area (above640 KB) during the boot routine.SRAMAbbreviation for static random-access memory. BecauseSRAM chips do not require continual refreshing, they aresubstantially faster than DRAM chips. SRAM is usedmostly for external cache memory.SVGAAbbreviation for super video graphics array. See alsoVGA.switchSee parameter.sync negotiationSync negotiation is a SCSI feature that allows the hostadapter and its attached SCSI devices to transfer data insynchronous mode. Synchronous data transfer is fasterthan asynchronous data transfer.syntaxThe rules that dictate how you must type a command orinstruction so that the computer will understand it.system boardAs the main circuit board, the system board usually con-tains most of your computer’s integral components, suchas the following:• Microprocessor• RAM• Expansion-card connectors• Controllers for standard peripheral devices, such asthe keyboard• Various ROM chipsFrequently used synonyms for system board are mother-board and logic board.system disketteSystem diskette is a synonym for bootable diskette.system memorySystem memory is a synonym for RAM.System Setup programSystem Setup program options allow you to configure yourcomputer’s hardware. Some options in the System Setupprogram require that you reboot the computer in order tomake a hardware-configuration change. Because the Sys-tem Setup program is stored in NVRAM, any options thatyou set remain in effect until you change them again.system.inifileWhen you start Windows, it consults the system.ini file todetermine a variety of options for the Windows operating
